The ventricular system

Question 1

What are the four ventricles that make up the ventricular system?

Answer 1

two lateral ventricles, third ventricle and fourth ventricle; these are interconnected by channels and are continuous with the central canal of the spinal cord and the subarachnoid space

Question 2

What cells line the ventricles- what are the choroid plexuses?

Answer 2

ependymal cells- a choroid plexus is a group of specialised ependymal cells within each ventricle that secrete cerebrospinal fluid (CSF)

Question 3

What is the route of flow in the ventricular system?

Answer 3

lateral ventricles -> interventricular foramen -> third ventricle -> cerebral aqueduct -> fourth ventricle -> median and lateral apertures -> subarachnoid space

Question 4

lateral ventricles

Answer 4

largest cavity in the ventricular system

Question 5

interventricular foramen

Answer 5

at the midline of the brain, channels contain choroid plexus

Question 6

third ventricle

Answer 6

in the midline between the left and right lateral ventricles, a median cleft between the 2 thalami

Question 7

cerebral aqueduct

Answer 7

within the midbrain (mesencephalon)- dorsal to the pons and ventral to the cerebellum

Question 8

fourth ventricle

Answer 8

within the pons or in the upper part of the medulla, characteristic diamond-shape in cross sections

Question 9

How is CSF returned to the venous system?

Answer 9

returned via the arachnoid villi- these are sections of arachnoid mater which project into the dural venous sinuses

Question 10

What are subarachnoid cisterns?

Answer 10

around the base of the brain the distance between the arachnoid mater and pia mater is increased in some areas forming subarachnoid cisterns- the cisterns contain greater amounts of CSF, arachnoid trabeculae and some cranial nerve roots

Question 11

What are the names of the subarachnoid cisterns (5)?

Answer 11

interpeduncular cistern, quadrigeminal cistern, chiasmatic cistern, pontocerebellar cistern, cerebellomedullary cistern

Question 12

Interpeduncular cistern

Answer 12

located between the cerebral peduncles of the midbrain

Question 13

Quadrigeminal cistern

Answer 13

located between the posterior part of the corpus callosum and the cerebellum, contains parts of the great cerebral vein and the pineal gland

Question 14

chiasmatic cistern

Answer 14

lies inferior and anterior to the optic chiasma- contains the dessucation of the optic nerve fibres

Question 15

pontocerebellar cistern

Answer 15

lies anterior to the pons

Question 16

cerebromedullary cistern (cisterna magna)

Answer 16

the largest cistern, located between the cerebellum and the medulla